Annealing leer



H. L. DlxN ANNEALING LEER July 8 1924.

Filed urch 2a 2 ShegtS-Sheet l' IIIIII July 8, 1924 1,500,609

H DIXON ANNEALING LEER Filed March 2S: 1921 2 sheds-shea a Patented .ulyI 8,' 1924.

UNITED srarasraraNT oar-ica HENRY L. mxomor DonnoN'r, l

or Ummm, rmsynvnmn,

PENNSYLVANIA, Assioma To l ANNEALING Application mea :laren 2s, 1921-.semina-153,218.

Figure 1 igure 3 is a view simllar to Flgure 2,'

showing a modification; c

Figure 4 is a view similar to Flgure l,

showing another modification; and l Figure 5 is a section oni/the lineV-V of re 4. v Y

y invention has relation to annealing leers, and more particularly toleers of the' muflie type.

The object of m invention is to provide means of practical, andeiiicient character whereby a leer of this type may be heatedelectricall in a manner to insure the maintenance o the desiredtemperatures throughout the different portions of the leer.

Referring first to that of my invention shown in Figures 1 and 2, thenumeral 2 designates the annealing chamber of a glass annealing leer,and 3 a portion of the tunnel part of the leer. The heating chamber 2 1sprovided with ay series of internal flues 4 ,which extend entirelyaround the heating chamber and are preferably spaced longitudinally onefrom the other. lThese figues are shown as formed of hollow tiles of anysuitable character.

In accordance with my invention, each of these flues is lilled with somematerial 5 which will act as a resistance conductor for electriccurrents. For this purpose, I emloy a graphite in more or lesscomminuted orm, or a mixture of carbon and silica commonly-known askryptol, or any other suitable material of this same general character.Each flue is provided with terminals or electrodes 6 by means of whichan electric current may be assed through the resistance materialthereln. In the construction shown in Figures 1 and 2, the electrodes orterminals are shown as extending intoA opposite `tively around theA fluearranged in multiple.

lower corners ofthe lues,

intended to divide and take two paths n. L. Dixon company, n conroaArIoNor rnNNsYLvamn. f

the current beingv n through the resistance material from one Yelectrode to the other. The current flow beportioned, of the resistancemixture or its density.- The electric connections leadin to theelectrodes are shown as grouped Ain ca les, one of which current mayl becontrolled. y ever, limit myself 'to any particular arrange- 1s carriedthrough a rheostat 7 by which th'ei G5 I do not, how.-

ment of the electric circuits, as these may 'l be arranged in anysuitable in the art and, for each Hue regulation by any vwell In Figure3, applied to a leer'which is generally similar to that shown in Figures1 and 2, except that the heating. chamber 2i has a-iat instead of anarched top;

manner known 1f deslred, the current flow known means.

may be capable of separate- .the terminals or electrodes I have shown myinvention .f

6, instead of' coming in at opposite corners of the furnace,come in atthe central ortion of the bottom the other.

In the form of myy invention shown in of each ue, suitable insulatf '808 being interposed .between f Figures 4 and', instead of providing thelI heating chamber' 2b tinuous spacey 9 between the inner and outer wallsof the chamber, which is lled with a resistance material. Preferably,this space 9 is of decreasing sectional area from the re# l dischargeend of the heatingefect av gradual reduction ,y

05 are shown'as from the provision of means whereby the.

leer may beV electrically heated, the arrangement being such that thetemperatures-.may be readily controlled andheld at the desired with aseries of'separate flues extending/around it, I provide a conpoint. vTheuse of electric heat for. the purpose also eliminatesall danger-ofinyury to the ware being annealed, due to any products of combustiongetting into the annealing chamber. The resistance material, beingconfined in aninclosed s ace or spaces, 1s

excluded from .the atmosp ere, thereby preventing its combustion andenabling it to be used for an indefinite period.

It will be readily understood that my invention is susceptible of manyother modications within the spirit and scope of the appended claims.

'I claim:

1. An annealing leer of the mulile type,

having a heating chamber, and means for electrically heating saidchamber, said means being of diferent characteristics in differentportions of the chamber whereby dierent temperature conditions may bemaintained in different' portions thereof, substantially as described.

2. A glass annealing leer of 'the muile type, having a resistanceymaterial in the walls ofits heating chamber, said material bein ofdifferent conductivity in diierent portions of the furnace, and meansfor passing electric currents in multiple through such material,substantially asdescribed.

3. An annealing leer of the muffie type, having a `heating chamber` anda tunnel' in communication therewith, and, means extending substantiallyentirely around the heating chamber for electrically heating the same,said means having dierent portions of its body of differentcharacteristics to aliv tomatically regulate .the current iowtherethrough, substantially-as described.

4. A glass annealing leer of the mule type, having a resistance materialin the walls of its heating chamber, said material being of diii'erentconductivity in different 4portlons of the furnace, substantially asdescribed.

In testimony whereof, have hereunto setmy hand. l

emNaY L. Dixon.

